Field of the Invention
An embodiment relates to a facsimile apparatus and a control method of the facsimile apparatus.
Description of the Related Art
In recent years, an increasing number of facsimile apparatuses have been downsized using a semiconductor data access arrangement (DAA) for an interface circuit unit with a telephone line. When a line voltage is monitored using this DAA, a voltage is conventionally measured when a user brings an external telephone into off-hook, and the measured voltage is used as a reference voltage. The DAA then detects a line voltage and compares the detected line voltage with the reference voltage to detect off-hook state. When these voltages are approximately equal, the DAA determines that off-hook is detected as discussed in Japanese Patent Application Laid-Open No. 2004-289315.
However, according to such a conventional technique, it is necessary to measure and set a line voltage by user operation at the time of installation. Therefore, it is necessary to set a line voltage again by the user operation, when the user switches to another line, or when the line voltage varies, or when the external telephone is changed. This operation complicated and may lead to false detection.
For example, in a case where the user change the external telephone to another telephone, after a line voltage is decided as an off-hook detection voltage when the user brings the external telephone into off-hook at the time of installation, a line voltage at off-hook time after this change is different from the determined line voltage. This may lead to off-hook false detection.